Bearing for crushers



Oct. 8, 1940.

E. B. sYMoNs ET AL BEARING FOR CRUSHERS Filed Feb. 1?, 1958 2Sheets-Sheet l l zeyez'zard 2 429075 ,Sywams' Oscar C aruezeaer 1940- E.B. SYMONS El AL BEARING FOR CRUSI'IERS Filed Feb. 17, 1938 '2Shoetgu-Sheet 2 a 2am r t IM grammatically in the Patented Oct. 8, 1940UNITED STATES PATENT OFFICE BEARING FOR CBUSHERS Edgar B. Symons,Hollywood, Calif., and Oscar C.

Gruender, Milwaukee, Wis., assignors to Nordberg Manufacturing 00.,Milwaukee, Wis., a

corporation of Wisconsin Application February 17,

8 Claims.

This invention. relates to an improvement in bearing means for gyratorycrushers and has for one purpose to provide bearing means which shallhave a minimum tendency to burn out orwear under intermittent load.

Another p p se is the provision of improved means for maintaining anefiective actuating contact between the eccentric and the shaft of agyratory crusher.

Other purposes will appear from time to time in the course of thespecification and claims.

The invention is illustrated more or less diaaccompanying drawings,wherein: l V

Figure 1 is a vertical axial section; Figure 2 is a section on the line2-2 of Figure 1;

Figure 3 is a diagrammatic horizontal section illustrating therelationship of the crushing cavity to the bearing means for the crushershaft, parts being shown without load;

Figure 4 is a similar diagrammatic section diagrammatically illustratingthe eifect of a crushing load; and i Figure 5 is a'vertical axialsection through the shaft and eccentric illustrating the clearancedimensions on a somewhat enlarged scale.

Like parts are indicated by like symbols throughout the specificationand drawings.

Referring to the drawings, I generally indicates any suitable base uponwhich the crusher may be supported. 2 indicates a circumferentiallyextending main frame having an upwardly and outwardly extending flange 3upon which seats a ring 4 having an inwardly screw-threaded portion 5. 6indicates an outwardly screwthreaded bowl support in mesh with thethreads on the member 5 whereby the parts may be vertically adjusted inrelation to each other. I

hook-shaped lugs 5, U-bolts 3, locking nuts I0 and adjusting shims Ii.The .member 4 is normally held fixed in relation to the main frame 2 bythe,

following structure: an upper ring l2, a lower ring I3 are penetrated bysecuring rods I4 headed as at above the top of the member 4 and providedwith nuts or limiting abutments it below the lower ring l3. I! arecoiled springs compressed between the rings 12 and I3. II are anysuitable guiding members interposed between the members 3 and 4 havingdownwardly extending portions l9 penetrating the springs II. It will beunderstood that the normal effect 01' the springs I1 is to hold the ring4 and thus the upper portion 6 and thebowl I fixed in relation to themain frame 2 while permitting the bowl or bowl liner I to recede whensubjected to predetermined excess crushing stresses.

is an eccentric sleeve connected to the main 1938, Serial No. 190,934

frame 2 in any suitable manner as by the spider or connecting portions2i. 22 is any suitable bearing member or bushing which may for examplebe, of bronze.

23 is an eccentric sleeve rotating within the bearing 22. 24 is abushing or bearing of bronze or the like positioned within the eccentric23 and providing a cavity or aperture 25 in which. is positioned thecrusher shaft 26 herein shown as tapered. As will be clear from Figure 1and from the diagrams, Figures 3 and 4, the inner diameter'of the sleeve24 or the space 25 is excessively greater than the greater portion 30 isclosed by an upper closure plate 3| upon which is supported an upwardlyconcave spherical bearing member 32 which receives the correspondingdownwardly convex spherical bear' ing surface 34 of the crushing headgenerally indicated as 33. 35 is any suitable crushing mantle which maybe held down for example by the top plate 35, the details of which formno part of the present invention. We may provide any suitable meansformaintaining a constant and adequate supply of oil in the spaces 25 and22a and in their communicating passages. We illustrate, for example, anoil inlet passage which may be supplied by oil from any suitable storageand pumping means. 4| is any suitable. oil outlet pipe whereby theconstant circulation of oil may be maintained through the machine; Thedetails of the oil passages are not of themselves part of the presentinvention, but we indicate the main oil passage 42 in the shaiftv 26which communicates with a passage 43 in the head and extends to thespherical bearing 32, 34. Oil may circulate thence over the gear 21 andpinion 28 and back to the outlet 4|. It will be understood, however,that by any suitable means we maintain a constant and preferably. fullsupply of oil in the spaces 22a and 25 and the employsive clearancebetween the sleeve 24 shaft 26. We fill the space left by these excesaneccentric, owing to the eccentric aperture therein defined by the sleeve24.

The use and operation of our invention are as follows:

In gyratory crushing, and particularly in crushing with the so-calledgyra-tory cone crushers, the problem of maintaining a proper bearingrelationship between the crusher shaft and the eccentric has at timesbeen difficult. The bearing problem differs from that of an ordinaryrotating shaft because in the first place the load is highlyintermittent and irregular. As material to be crushed is dumped into thespace between the opposed crushing members I and 35, it is in manyinstances not uniformly distributed; also the load fluctuates whereirregular feed is employed and may differ from instant to instant andfrom point to point about the circumference of the crushing cavity. Wefind it advantageous to cope with and take advantage of thisintermittent load by employing excess clearances, not only between theshaft 26 and the bearing sleeve 24, but between the eccentric 23 and thebearing sleeve 22. The excessive clearance between the eccentric 23 andthe sleeve 22 necessitates excesand the sive clearances with a body ofoil which has an effect radically other than that of the normalviscosity of the oil in a bearing having ordinary clearances.

Referring for example to Figure 3, where the bearings and crushingcavity are diagrammatically shown as roughly concentric, the machine maybe considered as running empty, the shaft 26 will be centrifugallydisplaced in its bearing, and the eccentric 23 will be centrifugallydisplaced in its bearing, taking the positions shown. Owing to the factthat the cavities are filled with oil, there will be a slight clearanceat the close side, which has been diagrammatically increased to indicatethat the oil prevents any metal to metal contact. When no rock is beingfed into the machine, there is nothing to prevent the parts fromcentrifugally taking the positions in which they are diagrammaticallyshown in Figure 3.

Referring to Figure 4, when the mantle 35 pinches a rock X against thebowl liner 1 and begins to apply pressure, then the shaft 26 moveswithin the eccentric and the eccentric 23 moves within the sleeve 22 tothe positions inwhich they are shown in Figure 4. However, in takingthis position, the eccentric will roll in its hearing as it is drivenfrom the shaft 29 and will climb the film of oil so rapidly that it willnot be displaced before the pressure has been released and the eccentriccan again start going back. This intermittent rolling of the eccentricbuilds up a film of oil thicker than is possible in any bearing whereviscosity alone is used. We are therefore depending upon displacement ofoil rather than upon mere viscosity of oil, and the very action of theeccentric in rolling within its outer bearing tends to thicken the filmof oil between it and the bearing 22 at the point of pressure at everymove of the eccentric. The mass of oilinvolved is so great that themovement of the eccentric caused by compression against the stone X isineffective to force the eccentric 23 into a metal to metal contact withthe surrounding bearing sleeve 22, and heating and damage to the opposedbearing surfaces is positively prevented. We wish to emphasize that theeffect of rolling the eccentric within its bearing against a large bodyof oil under compression is quite different from the effect obtained bythe employment of normal clearances. In the usual hearing, as employedfor example with rotating shafts, a very thin film of oil is more orless evenly distributed and the oil reaches the point of high pressuredue to its viscosity. We do not rely on viscosity at all but on thehydraulic effect obtained by rolling the eccentric over a very muchlarger mass or volume of oil, which volume is made possible by theexaggerated clearances between the opposed bearing surfaces.

As to the inner bearing between the shaft 26 and the surrounding sleeve24, the shaft does not roll as the eccentric does, but its displacementis so rapid and intermittent that, in connection with its increasedclearance, the same general effect is obtained and the same avoidance ofreliance on mere viscosity.

In considering actual dimensions, they differ from machine to machine,depending upon the size of the machine and the purpose for which it isemployed. As a schematic indication, we have illustrated clearances inFigure 5 as follows: between the eccentric 23 and the surroundingbearing sleeve 22 we show an outside theoretical radial clearance of a;of an inch which is uniform from top to bottom of the bearing surfaces.This permits a substantial lateral movement or slippage of the eccentric23 as it rolls about within its bearing. But this exaggerated movementof eccentric 23 demands compensation in similarly increased clearancesbetween the shaft 26 and its surrounding bearing 24. We illustrate aradial clearance of 3 2' of an inch at the top of the eccentric,increasing to A; l

inch at the bottom. We may express these clearances with the followingformula:

Assuming the distance A between the intersecting point of the axes ofthe eccentric sleeve bearing 22 and shaft 26 and the top of the bearingsleeve 24 equals the distance B which repre sents the length of thebearing sleeve 24, then the total lowermost clearance between the bellmouthed bearing sleeve 24 and the shaft 26 may be arrived at by addingthe top clearances indicated in Figure 5, and multiplying it by 2,representing the distance A,'equaling 1; plus the distance B, in thiscase also equaling 1. The formula is thus A major advantage in ourinvention is the effect of a larger clearance between the eccentric 23and the eccentric sleeve bearing 22. This very large clearance and therapid movement of the eccentric in relation to the eccentric sleevepermits the eccentric and shaft to dance as the intermittent load isapplied to the crushing cavity. This large clearance and rapid movementnecessitates the employment of a large clearance between the shaft 28and its surrounding sleeve 24, and in order to get a line contactbetweenthe shaft and the surrounding bearing at all positions of theeccentric, the clearance must increase progressively from top to bottomof the shaft. Thus, what we may call a bell mouth effect is necessitatedby the relationship between the eccentric 23 and the bearing sleeve inwhich it moves. The amount of taper or excess clearance necessarydepends upon the clearance between and the relative movement of theeccentric 23 and its surrounding sleeve. Therefore, in such largemachines as cone crushers having a head with a seven-foot bottomdiameter, we have to provide a very substantial bell mouth effect of theinner shaft bearing-or space 25 which permits an effective crushingthrust without springing of the shaft or any tendency to break theshaft, and at the same time allows the shaft to dance from one positionto another within its surrounding sleeve while maintaining at all timesan effective line contact.

I claim: v

1. In bearing means for gyratory crushers, an eccentric sleeve, aneccentric rotatably mounted within said sleeve and means for rotatingit, said eccentric having an eccentric aperture therein, a crushingshaft penetrating said aperture, a crushing head associated with saidshaft, supporting means for said crushing head adapted to guide saidhead for gyratory movement about a center located adjacent the top ofsaid head, the aperture of the eccentric being inclined in relation totheaxis of rotation of said eccentric, the clearance between theeccentric and eccentric sleeve substantially exceeding normal bearingclearances, the clearance between the crusher shaft and the opposed wallof the aperture of the eccentric substantially exceeding normal bearingclearances and increasing progressively downwardly along said shaft, andmeans for maintaining a substantially continuous volume of -oilthroughout the space provided by said excess clearances, whereby asubstantial thickness of oil is maintained between the opposed metalparts at all positions of eccentric and shaft.

2. In bearing means forgyratory crushers, an eccentric sleeve, aneccentric rotatably mounted within said sleeve and means for rotatingit, said eccentric having an eccentric aperture therein, a crushingshaft penetrating said aperture, a crushing head associated with saidshaft, supporting means forsaid crushing head adapted to guide said headfor gyratory movement about a center located adjacent the top-of saidhead, the aperture of the eccentric being inclined in relation to theaxis of rotation of said eccentric, the clearance between the eccentricand eccentric sleeve substantially exceeding normal bearing clearancesand being substantially uniform from top to bottom of the eccentric, theclearance between the crusher shaft and the opposed wall of the apertureof the eccentric substantiallyexceeding normal bearing clearances andincreasing progressively downwardly along said shaft, and means formaintaining a substantially continuous volume of oil throughout thespace pro vided by said excess clearances, whereby a substantialthickness of ofl is maintained between the opposed metal parts at allpositions of eccentric and shaft. l

3. In a gyratory crusher and bearing means therefor a crushing shaft, acrushing head,

means for constraining-said head to gyratory movement about a centerlocated adJacent the top of the head, and means .for gyratlng said head,including an eccentric sleeve, an eccentricrotatably mountedv withinsaid sleeve and means for rotating it, said eccentric having aneccentric aperture therein into which said crushing shaftpenetrates,said aperture being inclined from the vertical, the clearance betweenthe eccentric and the eccentric sleeve substantially exceeding normalbearing clearances whereby said eccentric sleeve may move laterally inaddition to its rotary movement, the clearancebetween the crush-,-

.er shaft and the opposedwall of the aperture of the eccentricsubstantially exceeding normal bearing clearances, said clearanceincreasing progressively downwardly along said shaft, whereby at allpositions of the eccentric during its lateral movement an effectivebearing connection is obtained between the opposed portions 5' of theshaft and eccentric, and means for maintaining a substantiallycontinuous volume of oil throughout the space provided by said excessclearances, whereby a substantial thickness of oil is maintained betweenthe opposed metal parts at all positions of the eccentric and shaft,said volume of oil being sufficient to damp. the movement of theeccentric within the eccentric sleeve, and of the shaft within theeccentric aperture.

4. In bearing means for gyratory crushers, an eccentric sleeve, aneccentric rotatably mounted within said sleeve and means forrotating it,said eccentric having an eccentric aperture therein, a crushing shaftpenetrating said aperture, a crushing head associated with said shaft,supporting means for said crushing headadapted to guide said head forgyratory movement about a center located above the top of the eccentric,the aperture of the eccentric being inclined in relation to the. axis ofrotation of said eccentric, the clearance between the crusher shaft andthe opposed wall of the aperture of the eccentric increasingprogressively downwardly along said shaft, and means for maintaining asubstantially continuous layer of oil throughout the space provided bythe clearance between the crusher shaft and the eccentric, of sufficientdepth and volume to respond hydraulically to relative movement of thecrusher shaft and eccentric.

5. In bearing means for gyratory crushers, an

eccentric sleeve, an eccentric rotatably mounted center located adjacentthe top of said head, the

aperture of the eccentric being inclined in relation to the axis ofrotation of said eccentric, the clearance between the eccentric andeccentric sleeve being substantially uniform from top to bottom of theeccentric, the clearance between the crusher shaft and theopposed wallof the aperture of the eccentric increasing progressively 50 downwardlyalong said shaft, and means for maintaining a substantially continuousvolume of oil throughout the space provided by said, clearances, wherebya layer of oil of sufficient depth and volume to respond hydraulicallyto relative movement of the crusher shaft and eccentric or of eccentricand eccentric sleeve is maintained at all positions of the parts.

6. In a gyratory crusher, a crushing-head, a shaft extending downwardlytherefrom, an ec- 00 centrically aperturedlmember surrounding said

